Support for backrest and seat of seat furniture

ABSTRACT

A back and waist support device mounted on a seating furniture equipment such as, for example, a chair or a legless chair is disclosed. The device includes a first arm for supporting a longitudinally extending first projection arranged for forcedly pressing the back of a user and a second arm for supporting a longitudinally extending second projection arranged for forcedly pressing his waist, as well as springs arranged on the first arm and second arm so as to urge the first projection and second projection in a direction of forcedly pressing the back and waist, respectively, resulting in being constructed in a manner to be pivotally movable. The first and second arms per se each may be constructed into an elastic structure, to thereby eliminate arrangement of the springs. Also, an angle between the first arm and the second arm may be adjustable. Such construction permits the first projection and second projection to effectively forcedly press the back of a user and his waist irrespective of a posture of the user such as, for example, his sitting with a slouch, his sitting forward on a seat or the like, so that the user may throw out his chest and stretch his backbone while relaxing his body, resulting in relieving his fatigue.

TECHNICAL FIELD

This invention relates to a back and waist support device for a seatingfurniture equipment, and more particularly such a back and waist supportdevice adapted to press the back and waist of a user to permit the userto throw out his chest, so that the user may straightly stretch hisbackbone to correct his posture and concurrently may safely support hiswaist without any burden thereon.

BACKGROUND ART

In general, a seating furniture equipment such as a chair, a sitting orlegless chair, or the like is constructed so as to permit a user tocomfortably sit thereon when he leans or rests against a backrest of theseating furniture equipment. However, when the user sits on the seatingfurniture equipment while stooping or sits forward on the equipment,resulting in his posture being unnatural, the equipment causes him to besimply tired, resulting in the user failing to comfortably sit on theequipment for a long period of time and his health being adverselyaffected.

Thus, it is desired that a user sits on the seating furniture equipmentwhile keeping his chest thrown out, his backbone straightly stretchedand his body relaxed to the utmost. This permits the user to relieve hisfatigue and relax his body. Also, such a seated posture permits the userto relax his muscle and nerve, so that he may get rid of stress.

Unfortunately, in general, it is highly difficult for the user to take aposture of throwing out his chest and straightly stretching his backboneduring his sitting.

In view of the foregoing, the applicant proposed a seating furnitureequipment constructed as shown in FIGS. 1 and 2. More particularly, theseating furniture equipment proposed includes a longitudinally extendingor elongated projection for concurrently supporting the back M and waistH of a user M. The longitudinally extending projection includes a firstlongitudinal projection member x for supporting the back B of the userand a second longitudinal projection member y for supporting his waist Hwhich are arranged separately from each other, as well as an angleadjusting mechanism z arranged therebetween. The first and secondprojection members x and y are connected to each other through the angleadjusting mechanism z in a manner to be pivotable in relation to eachother and held at a desired angle with respect to each other. Theproposed seating furniture equipment is disclosed in Japanese PatentApplications Nos. 153428/1988 and 201035/1988.

The seating furniture equipment proposed is constructed so as toconcurrently support both back B and waist H of a user, so that he maycomfortably sit on the seating furniture equipment for a long period oftime without being tired; because it permits the user to throw out hischest and stretch his backbone, to thereby relax his body during hissitting. Thus, the user may relieve his fatigue.

The seating furniture equipment is so constructed that the firstprojection member x is fixed. Thus, it exhibits an effective functionwhen the user sits on the seating furniture equipment while forcing orleaning his back against the first projection member x as shown in FIG.2. However, when the user sits on the equipment with a slouch, forexample, while resting his elbows upon a desk, it causes separation ofthe back B of the user from the first projection member x, resulting infailing to permit the first projection member x to effectively force theback B. Also, the first and second projection members x and y arearranged so as to extend in a longitudinal or vertical direction. Sucharrangement exhibits an effective action because it permits the user'schest to be thrown out when the user sits on the equipment while leaningthe back B and/or waist H against a backrest of the equipment. However,in this instance, it lightly contacts the first and second projectionmembers x and y with the back B and waist H without pressedly forcingthe former against the latter, resulting in failing to exhibit asignificant massage action or pressure therapy.

In view of the foregoing, an object of the present invention to providea back and waist support device for a seating furniture equipment whichis capable of effectively forcedly pressing the back and waist of a userby arranging arms so as to support a first projection and a secondprojection and arranging springs on the arms so as to urge the arms in adirection in which the first and second projections are forcedly pressedagainst the back and waist of the user.

It is another object of the present invention to provide a back andwaist support device for a seating furniture equipment which it soconstructed that arms each act as an elastic means or an angle betweenthe arms is adjustable.

It is a further object of the present invention to provide a back andwaist support device for a seating furniture equipment which is soconstructed that first and second projections are varied inconfiguration or exhibit a massage action or arms are varied in lengthin conformity to a physique of a user or his figure.

DISCLOSURE OF INVENTION

In accordance with the present invention, a back and waist supportdevice for a seating furniture equipment is provided. The seatingfurniture equipment includes a spring for urging a first projection forsupporting the backbone of a user in a direction in which the firstprojection presses his back and a spring for urging a second projectionfor supporting his waist in a direction in which the second projectionpresses the waist. Such arrangement of the springs permits the first andsecond projections to forcedly press the back and waist by elastic forceof the springs when the user merely sits in the seating furnitureequipment, so that he may naturally thrown out his chest and stretch hisbackbone.

Also, the present invention may be constructed in such a manner that thearms per se may exhibit elastic force rather than arrangement of thesprings. Also, an angle between the first arm and the second arm may beadjustable. Alternatively, the angle may be kept constant or fixed. Inany event, such construction exhibits an effective massage function.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view showing a conventional seating furnitureequipment including a first projection member and a second projectionmember.

FIG. 2 is a side elevation view showing the manner of operation of theconventional seating furniture equipment of FIG. 1.

FIG. 3 is a side elevation view showing a first embodiment of a back andwaist support device for a seating furniture equipment according to thepresent invention.

FIG. 4 is a side elevation view showing a second embodiment of a backand waist support device for a seating furniture equipment according tothe present invention.

FIG. 5 is a side elevation view showing a third embodiment of a back andwaist support device for a seating furniture equipment according to thepresent invention.

FIG. 6 is a side elevation view showing a fourth embodiment of a backand waist support device for a seating furniture equipment according tothe present invention.

FIG. 7 is a side elevation view showing a fifth embodiment of a back andwaist support device for a seating furniture equipment according to thepresent invention.

FIG. 8 is a side elevation view showing a sixth embodiment of a back andwaist support device for a seating furniture equipment according to thepresent invention,

FIG. 9 is a side elevation view showing a seventh embodiment of a backand waist support device for a seating furniture equipment according tothe present invention.

FIG. 10 is a side elevation view showing an eighth embodiment of a backand waist support device for a seating furniture equipment according tothe present invention.

BEST MODES FOR CARRYING OUT INVENTION

Now, a back and waist support device for a seating furniture equipmentaccording to the present invention will be described in detail withreference to the accompanying drawings.

Referring first to FIG. 3, a first embodiment of a back and waistsupport device for a seating furniture equipment according to thepresent invention is illustrated. A back and waist support device of theillustrated embodiment includes a base plate 1 mounted at any desiredvertical position on a backrest of a seating furniture equipment or, forexample, a chair by means of a commercially available detachablemounting element. Also, the back and waist support device includes afirst arm 4 and a second arm 5 pivotably mounted at one end thereofthrough shafts 2 and 3 on the base plate 1, respectively. The first arm4 and second arm 5 are mounted at the other end thereof or a free endthereof with a longitudinally extending first projection 8 forsupporting a backbone of a user and a second longitudinally extendingsecond projection 9 for supporting a waist of the user through shafts 6and 7, respectively. The first projection 8 and second projection 9 maybe fixedly mounted on the first arm 4 and second arm 5, respectively.However, as shown in FIG. 3, the projections 8 and 9 may be mounted onthe shafts 6 and 7 in a manner to be pivotally moved about the shafts 6and 7, respectively. Such latter construction permits an angle of thefirst projection 8 and second projection 9 to be desirably variablyadjusted or set when the first and second projections forcedly press theback and waist.

The first projection 8 and second projection 9 each are constituted ofan elastic member made of urethane foam or the like and an outerpackaging sheet member such as fabric, vinyl leather or the like forcovering the elastic member. The first projection 8 and secondprojection 9 may be formed into any suitable shape in section such as,for example, a rectangle, a trapezoid, a semicircle or the like so longas they are projected toward the back and waist.

The back and waist support device of the illustrated embodiment alsoincludes springs 10 and 11 which are arranged between the first arm 4and the base plate 1 and between the second arm 5 and the base plate 1so as to elastically force the first arm 4 and second arm 5 in adirection in which the first projection 8 and second projection 9 areforcedly pressed against the back and waist of a user sitting on theequipment, respectively. In the illustrated embodiment, the spring 10 isarranged so as to force the first arm 4 in a counter-clockwise directionin FIG. 3 and the spring 11 is arranged so as to urge the second arm 5in a clockwise direction. Thus, the first projection 8 and secondprojection 9 are permitted to be forcedly pressed against the back andwaist of the user by elastic force of the springs 10 and 11, when hesits on the seating furniture equipment, resulting in the back and waistof the user being rested upon the projections 8 and 9.

Thus, when the user sits on the seating furniture equipment to rest hisback and waist on the first and second projections 8 and 9,respectively, the projections permit a pressure to act on the back andwaist using elastic force of the springs 10 and 11, to thereby exhibit amassage function.

Referring now to FIG. 4, another embodiment of a back and waist supportdevice for a seating furniture equipment according to the presentinvention is illustrated, which is directed to an improvement in theback and waist support device shown in FIG. 3. More specifically, a baseplate 1 is divided into two base plate members 1a and 1b, which arepivotally connected to each other through an angle adjusting mechanism12 and held at any desired angle therethrough.

The embodiment described above with reference to FIG. 3 is soconstructed that the first projection 8 and second projection 9 may beheld in position under a balance of elastic force between the springs 10and 11. Use of only elastic force of the springs 10 and 11 in theembodiment of FIG. 3 causes force at which the first and secondprojections 8 and 9 press the back and waist to be proportionally varieddepending on an angle of pivotal movement of the first and second arms 4and 5.

More particularly, positioning of the first and second arms 4 and 5while keeping an angle therebetween reduced causes force at which thefirst projection 8 presses the back of the user to be reduced, whereasthat while keeping the angle increased causes the force to be increased.This is likewise true of force at which the second projection 9 pressesthe waist of the user.

In the embodiment of FIG. 4, as described above, the base plate 1 isvertically divided into two such base plate members 1a and 1b and theangle adjusting mechanism 12 is arranged therebetween so as to hold thebase plate members 1a and 1b relative to each other at any desiredangle. Such construction permits an angular interval between the firstarm 4 and the second arm 5 and therefore that between the firstprojection 8 and the second projection 9 to be set as desired.

The angle adjusting mechanism 12 may be constructed in any suitablemanner such as, for example, a manner of carrying out rotation of aratchet gear in both normal and reverse directions by means of a lover12a.

Referring now to FIG. 5, a further embodiment of a back and waistsupport device for a seating furniture equipment according to thepresent invention is illustrated. A back and waist support device of theillustrated embodiment is so constructed that a base plate 1 mounted ona backrest of a seating furniture equipment in the form of a chair ispivotably mounted thereon with a first arm 14 and a second arm 15through a single shaft 13. Also, in the illustrated embodiment, thefirst arm 14 and second arm 15 per se each are made of an elasticmaterial. A base plate 1 may be divided into two base plate members ofwhich an angle is adjustable as in the embodiment shown in FIG. 4.However, in the illustrated embodiment, an angle adjusting mechanism 16is mounted on the shaft 13.

Preferably the first arm 14 and second arm 15 may be made of such anelastic steel or plastic material as widely used for a spring, resultingin exhibiting satisfactory elasticity and tapered as required as shownin FIG. 5. Also, a first projection 8 and a second projection 9 may bedesirably arranged in a manner to be pivotally movable about shafts 17and 18, respectively, as shown in FIG. 5.

Referring now to FIG. 6, still another embodiment of a back and waistsupport device for a seating furniture equipment according to thepresent invention is illustrated. In the illustrated embodiment, a firstprojection 8' and a second projection 9' each are formed into acylindrical shape. Such configuration of the first and secondprojections 8' and 9' permits a feeling of contact of the body of a userwith the projections to be kept unvaried irrespective of a degree ofopening of the first am 14 and second arm 15. In this instance, thefirst projection 8' and second projection 9' are intended to act on acenter of the back of the user (his lumber, thoracic vertebrae andbackbone) and on his waist, respectively, thus, they are desirablyformed into a reduced width.

Referring now to FIG. 7, yet another embodiment of a back and waistsupport device for a seating furniture equipment according to thepresent invention is illustrated. In the illustrated embodiment, a shaft13 is arranged in a manner to be rotatable while keeping a first arm 14and a second arm 15 at a constant angle. More specifically, in theillustrated embodiment, the shaft 13 is supported on a plain or slidebearing 19, so that a balance of force between a first projection 8' anda second projection 9' may be ensured, resulting in a feeling in use ofa seating furniture equipment being improved and positional relationshipbetween the first and second projections 8' and 9' and a backrest of theequipment being balanced irrespective of an angle of the backrest andmotion of the body of a user.

Referring now to FIG. 8, even another embodiment of a back and waistsupport device for a seating furniture equipment according to thepresent invention is illustrated. In the illustrated embodiment, a firstarm 20 and a second arm 21 each are so constructed that a length thereofis adjustable or variable. More particularly, in the illustratedembodiment, the first arm 20 and second arm 21 are divided into two armmembers 20a and 20b and two arm members 21a and 21b, respectively. Thearm members 20a and 21a each are formed into a reduced thickness ordiameter and the arm members 20b and 21b each are formed into anincreased thickness or diameter. The arm members 20a and 20b areconnected to each other at any one of a plurality of connectionpositions selected as desired by means of a bolt 22, resulting in thefirst arm 20 being variable in length. Likewise the arm members 21a and21b are connected to each other at any one of a plurality of connectionpositions selected as desired by means of a bolt 23, resulting in thefirst ann 21 being likewise variable in length. Such constructionpermits the back and waist support device of the illustrated embodimentto be accommodated to a figure of a user.

Referring now to FIG. 9, a still further embodiment of a back and waistsupport device for a seating furniture equipment according to thepresent invention is illustrated. The illustrated embodiment is soconstructed that any one of a first projection 8' and a secondprojection 9' is used. In the illustrated embodiment, an arm member 20areduced in diameter is detached from an arm member 20b increased indiameter, so that the first arm 20 is kept from being used.

Referring now to FIG. 10, a yet further embodiment of a back and waistsupport device for a seating furniture equipment according to thepresent invention is illustrated. A back and waist support device of theillustrated embodiment is constructed so as to further promote pressingof a first projection 8' and a second projection 9' against the back ofa user and his waist, to thereby further exhibit a massage function. InFIG. 10, a slider crank mechanism is shown by way of example. Moreparticularly, a piston 25 is arranged so as to be reciprocated about ashaft 24a of a motor 24, so that a first arm 14 and a second arm 15 maybe varied in angle, resulting in a first projection 8' and a secondprojection 9' massaging the back of a user and his waist, respectively.

Industrial Applicability

As can be seen from the foregoing, the back and waist support device ofthe present invention permits the first projection and second projectionto effectively forcedly press the back of a user and his waistirrespective of a posture of the user such as, for example, his sittingwith a slouch, his sitting forward on a seat or the like, so that theuser may throw out his chest and stretch his backbone.

What is claimed is:
 1. A back and waist support device for a chairhaving a seating surface and a backrest, comprising a longitudinallyextending first projection for supporting the back of a user and alongitudinally extending second projection for supporting the waist ofthe user, characterized in that:a first arm is arranged for supportingsaid first projection wherein the first arm extends laterally from agenerally center position of the backrest; a second arm is arranged forsupporting said second projection wherein the second arm extendslaterally from a generally center position of the backrest; springs arearranged on said first arm and second arm so as to urge said firstprojection and second projection in a direction in which said first andsecond projections forcedly press the back and waist, respectively; saidfirst and second arms each are arranged in a manner to be pivotallymoved about a separate shaft within a predetermined range, each shaftadapted for attachment to the backrest; a first base plateinterconnected between the first arm and the backrest; a second baseplate interconnected between the second arm and the backrest; and anangle adjusting mechanism disposed between the first base plate and thesecond base plate to permit the base plates to be pivotally moved andheld at any desired angle.
 2. A back and waist support device for achair having a seating surface and a backrest, comprising alongitudinally extending first projection, horizontally positioned forsupporting the back of a user and a longitudinally extending secondprojection, horizontally positioned for supporting the waist of theuser,characterized in that: a first arm is arranged for supporting saidfirst projection; a second arm is arranged for supporting said secondprojection; and said first arm and second arm each are pivotallyattached to a single shaft, said shaft adapted for operative attachmentto the backrest, and each arm comprised of an elastic material to urgesaid first projection and second projection in a direction in which saidfirst projection and second projection forcedly press the back of a userand his waist, respectively.
 3. The device of claim 2 further includinga single base plate wherein the base plate is interconnected between thefirst arm and the backrest and the base plate is also interconnectedbetween the second arm and the backrest.
 4. A back and waist supportdevice for a chair having a seating surface and a backrest, comprising alongitudinally extending first projection, horizontally positioned forsupporting the back of a user and a longitudinally extending secondprojection, horizontally positioned for supporting the waist of theuser,characterized in that: a first arm is arranged for supporting saidfirst projection; a second arm is arranged for supporting said secondprojection; and said first arm and second arm each are constructed so asto be variable in length, said first arm and second arm are pivotallyattached to a single shaft, and said shaft adapted for operativeattachment to the backrest.
 5. The device of claim 4 wherein the firstarm and second arm are divided into two arm members.
 6. The device ofclaim 5 wherein first arm member is telescopingly connected to thesecond arm member, and provided with a plurality of selective connectionpositions.